Monoazo dyestuffs of the benzothiazol series



United States Patent Ofi ice The present invention relates to monoazo dyestufis of the benzothiazol series which correspond to the formula II Z l Ri-M Rs-OaS wherein 1 R stands for an alkylene radical with 1 to 4 carbon atoms,

R for hydroxyalkyl, dihydroxyalkyl, alkoxyalkyl, acetoxyalkyl which may be further substituted, cyanoalkyl, difluoromethyl, trifluoromethyl, fluorated cyanoal'kyl, carbalkoxyalkyl or a carbamic acid alkyl ester radical,

R for an alkyl or alkylene radical with l to 4 carbon atoms or an amino group which may be substituted by one or two alkyl, aralkyl, cycloalkyl or aryl radicals which may contain further substituents,

R for hydrogen or alkyl with 1 to 4 carbon atoms,

R for halogen, nitro or the sulfonic acid group,

M for hydrogen, hydroxy or alkoxy, acetoxy which may be further substituted, or a carbamic acid ester radical,

Y for hydrogen, halogen, low molecular alkyl or alkoxy,

trifluoromethyl, tri-fiuoroacetyl amino or an alkanoylamino radical with not more than 18 carbon atoms, and

Z for hydrogen, halogen, low molecular alkyl or alkoxy or together with and the adjacent benzene nucleus ring.

The process for the production of the new monoazo dyestuffs of the benzothiazol series consists in diazotizing 1 mol of an amine of the formula a tetrahydroquinoline ILA 11) lugs.

peroxide bleaching, rubbing, decatizin 3,105,829 Patented Oct. 1, 1963 Certain of the amines of the Formula II must be diazotized under special conditions. Some of them -form very poorly soluble sulfates and therefore cannot be diazotized in concentrated sulfuric acid. In such cases \diazotization can be carried out, for example, in phosphoric acid.

The diazo compounds are coupled with the coupling components in an acid medium, which may be buttered if necessary.

A number of the new insoluble monoazo dyestuffs dye from aqueous suspension synthetic polyarnide fibers (e.g. nylon, Perlon, registered trademark), cellulose ester fibers (e.g. secondary cellulose acetate and cellulose triacetate), polyvinyl fibers, polyacrylonitrile fibers (e.g. Orlon, Acrilan, registered trademarks) and polyester fibers (e.-g. Terylene, Dacron, registered trademarks) in brilliant red and violet shades. 'Ihe dyeings are characterized by very good fastness to light, washing, perspiration, gas fumes, water and sea water, and are white dischargeable. Cotton, wool and viscose rayon are reserved.

In addition, some of the new dyestuffs are suitable ctor pigmenting lacquers, oils, and synthetic resins, and for dyeing man-made fibers in the mass. The shades they produce in spun-dyed cellulose acetate possess 'high fastness to light, washing, perspiration, water, sea water, soaping, cross dyeing, alkaline bleaching, oxalic acid, dry cleaning,

, and pressing.

Those of the new monoazo dyestuifs which contain free sulfonic acid groups dye wool, silk, animalized cellulosic fibers, and the polyamide fibers nylon, Perlon and Rilsan (registered trademarks), and also polyacrylonitrile fibers by the cuprous ion dyeing method. On these fibers they yield red or violet shades which are fast to light, washing, milling, sea water, perspiration, sublimation, pleating and heat setting.

This latter group of dyestutfs is also suitable for the pigmentation of lacquers, oils, synthetic resins, and the dyeing of man-made fibers in the mass, being applied where necessary after laking with suitable cations. In these materials the dyestuifs exhibit good fastness to light, gas fumes and wet treatments.

It may be noted that there was no reason to expect that brilliant red, violet and blue monoazo dyestuffs could be obtained from these new diazo compounds, because the comparable 2.6-disubstituted 1-aminobenzene-4-sultones and -sulfonic acid amides yield only dull orange monoazo dyestuifs.

The amines of the Formula II are 1 mol of a compound of the formula S 's-02S 6 7 1 produced by treating 13 V (II) A further process for the production consists in converting 1 mol of a compound of the formula S halogen-MS- CNH1 RP k N n) wherein R and R possess the aforecited meanings, the free amino group of which may be protected by a readily spltitable acyl radical, into sulfmic acid and alkylating this by the normal methods, or alternatively by reacting the aforesaid compound with ammonia, which may be substituted by alkyl, aralkyl, cycloalkyl or aryl radicals which may contain further substituents, and subsequently splitting off the acyl radical in the reaction product when present. This process of acid amide formation is carried out preferably in presence of an acid-binding agent or with the aid of an excess of the amine.

When an acyl radical is present it can be split olf in the normal way by alkaline or acid hydrolysis, preferably at high temperature. I The amines are isolated by one of the common basic operations, e.g. filtration, evaporation of the solvent, salting out, precipitation from the solvent with a suitable agent, etc., where necessary after neutralization of the hydrolysing solution.

The amines are valuable intermediate products which find employment in the production of dyestuffs and pharmaceutical products.

In the following examples the parts and percentages are by weight and the temperatures in degrees centigrade. The melting points are uncorrected.

Example 1: 5.5 parts of 2-amino-4-nitro-6-methylsulfonlybenzothiazol are ground with 200 parts of phosphoric acid and 300 parts of glass balls for 4 /2 hours in a glass flask. A fine suspension is formed which is separated from the glass balls and diazotized at 5 with 1.6 parts of solid sodium nitrite. After l /2 hours, 5 parts of N cyanoethyl N hydroxyethylaminobenzene are added with vigorous stirring upon which coupling takes place instantaneously. The dark blue suspension is diluted with 250 parts of water and the product filtered off, washed free of acid, and dried. It is obtained as a dark powder which dissolves in acetic acid ethyl ester to give violet solutions. The new dyestuif probably corresponds to the formula water.

are introduced into the bath at room temperature; the temperature is raised to in 1 hour and the bath main- 4 Applied from aqueous suspension at high temperature, preferably in presence of compounds with dispersing action, the dyestuif dyes cellulose acetate fibers in brilliant violet shades which have good fastness to light, gas fumes, sublimation, and wet treatments, and are readily dischargeable.

When in place of N-hydroxyethyl-N-cyanoethylaminobenzene, aliquot amounts of N-hydroxyethyl-N-difluoroethylarninobenzene or l-(N hydroxyethyl-N-cyanoethyl)- amino-3-methylbenzene are employed, similar dyestufis are obtained which possess virtually the same standard of light fastness.

Again, by using as coupling componentsLNN-di-(hydroxyethyl)=-amino-3-methylbenzene, 1-N.N-di (hydroxyethyl)-amino-3-acetylaminobnezene, l-N.N-di-(hydroxyethyl)-amino-3-acetylamino-G-methoxybenZene, 1-N.N-di- (acetoxyethyl) -amino-3-propionylaminobenzene, further dyestuffs of a slightly more bluish shade are obtained, some of which show better fastness to washing. Similar dyestuffs are obtained with 2-diazo-4-nitr0benzothiazol-6- sulfonic acid amides.

The 2-amino-4-nitro-6-rnethylsulfonylbenzothiazol used as diazo component is produced in the following manner:

22.8 parts of 2-amino-6-methylsulfonylbenzothiazol are dissolved in parts of 96% sulfuric acid at 10, about 4 hours being required for complete solution. After cooling to 5, 12.6 parts of a mixture of acids consisting of 50% of sulfuric acid and 50% of nitric acid are dropped into the solution. The nitration mixture is stirred for 3 hours at 0 and for the following 24 hours at 20, after which it is run into 1000 parts of icewater. The yellow suspension is filtered oif, washed free of acid, and dried. The Z-amino-4-nitro-6-methylsulfonylbenzothiazol formed melts at 294-305" in the crude state.

A dyebath is prepared with 1 part of the above-described dyestufi dispersed with the aid of Turkey red oil, 6 parts of a sulfonated fatty alcohol and 3000 parts of 100 parts of secondary cellulose acetate fabric tained at this temperature for a further hour. After this time the dying process is completed and the material is removed, rinsed and dried.

In the following Table 1 further monoazo dyestufls are recited which may be produced in an analogous manner and which correspond to the formula S S Z /CHnCHz-CN /RiM C N=N N\ C CH2CH2OH 1 CHr-Ra I N 1 N Y NO: NO:

Table 1 Exzliqmple R1 Y R3 R4 M R2 Z Shade H CH3 H H CHz-CN H Red violet. H CH3 H H CHz-CN H D0. H CH3 H H CHz-CN H D0. H CH3 H H CHz-CN H D0. CH3 CH3 H H CHs-CN H Violet. CH3 CH3 H H CHz-O-C O-CHa H D0. CH CH3 H H CH(OH)CHz-OH H DO. CH3 OH; H H CHF2 H D0. CH3 CH3 H H CFa H Red violet. H CH3 H H CH CF1QCN H Ruby. CH3 CH3 H H CHz-C O-O-CHs H Violet. H OH; H H CHz-C 0-C-CH3 11 Red violet. H NH-CH3 H H CHz-CN H Do. H N(CH3)2 H H CHz-CN H D0. H N(CH3) CHz-CHz-OH H H CHz-CN H D0. H NH-GHa-OHz-CHz-O-CHa H H CHz-CN H D0. H NH-CHs H H CHz-CN H D0. H N(CH3)2 H H CHr-CN H D0. H NH-CHz-CHz-CN H H CHs-CN H DO. H CH3 CH: CH CHz-CN V H DO. NH-C 0-CH3 CH3 H H CH(OH)CHz-OH H Violet. NH-C O-GHa N(CH3)2 H OH CHz-OH OCHs Blue. NH-C 0-CH3 N(-CH3)2 H H CH(C'H)CHz-OH O CaHr, D0 NH-C O-GFs CHa H OH C rOH CH3 Violet. NH-CO-C'Ha CH3 H H CzHa-OH C1 D0; NH-C O-GHs NH-CH: H OH Br D0.

Table I-Continued Example 60: 45 parts of concentrated sulfuric acid are heated to 60 and at this temperature 3.8 pants of sodium nitrite are added. The mixture is stirred for 1 hour at 60-70 and then cooled to 10, at which temperature is added a finely ground suspension of 15.4 parts of the Z-amino-6-methylsulfonylbenzothiazol-4-sulfonic acid, in 84 parts of glacial acetic acid and 16 parts of propionic acid. The diazotizing mixture is stirred for 3 hours at 10-20", then 9 parts of N-ethyl-N-hydroxyethylaminobenzene are added. After stirring for 15 minutes the mass is poured into a mixture of 250 parts of ice and 200 parts of Water, whereupon the dark colored product precipitates. It is filtered oil, Washed until of neutral reaction, and dried. The new dyestuif does not melt even at 250 and is insoluble in acetone. At low temperatures it is moderately soluble, and at high temperatures well soluble, in 10% sodium hydroxide solution. It dyes wool, silk and nylon from an acetic acid bath in bright red-violet shades, but reserves hydrophobic fibers in this dyeing medium.

In an analogous manner the dyestufi SOaH and

HaC-OgS- SOaH CHz-CHa-CN CHr-CHz-O-C O-CH:

CHz-CHrCN are especially suitable, as are the lakes prepared from them.

The 2 amino-6-methylsulfonylbenzothiazol-4-sulfonic acid is obtained as follows: 7

100 parts of Z-amino-6-methylsulfonylbenzothiazol are added to 1000 parts of oleum with a content of 27% of S The temperature of the mixture increases by selfgeneration of heat to 48, at which point completej solution occurs. It is stirred for 2 /2 hours at 48 and for the next hours at room temperature. The homogeneous solution is run onto 3500 parts of ice, upon which the reaction product precipitates, While small amounts of the unmodified starting product remain in solution. The

resultant 2-amino-6-methylsulfonylbenzothiazol-4-sulfonic acid is filtered olf, washed until of neutral reaction, and dried. The new acid does not melt even at 250; it dissolves in an aqueous solutionof dimethylamine, but not in dilute acids nor in dimethylformarnide or phosphorus oxychloride.

Example 61: 15.35 parts of 2-am ino-4-bromo-6-methylsulfonylbenzothiazol are diazotized as described in Example 60. The diazo compound obtained is added to a solution of 10 parts of N-cyanoethyl-N-hydroxyethylaminobenzene in 100 parts of glacial acetic acid. After stirring for minutes at the mixture is poured onto 250 parts of ice and 200 parts of water, upon which the new dyestuft precipitates as a dark red powder. It is filtered oft, washed until of neutral reaction, and dried. It is well soluble in alcohol, dioxane and ethyl acetate, giving bluish red solutions. The dyestufi dyes cellulose acetate and triacetate and polyester fibers from aqueous suspension in brilliant bluish red shades which have very good fastness to light, Washing, perspiration, sublimation and pleating, besides being readily dischargeable. Cotton, viscose and Wool are reserved. j I

Z-amino-4-bromo-6-methylsulfonylbenzolthiazol is prepared as follows: f

46 parts of 2-amino-6-methylsulfonylbenzothiazol are dissolved in a warm mixture of 766 parts of glacial acetic acid and 144 parts of propionic acid. The solution is cooled to 0 with stirring, causing the amine to be precipitated in a fine form. A solution of parts of bromine in parts of glacial acetic acid and 10 parts of propionic acid is then added in portions. The reaction mixture is stirred overnight at room temperature and subsequently for 1 hour at The yellow bromination product formed is filtered oil at room temperature,

washed thoroughly with glacial acetic acid and then with water, and dried at 100 with vacuum. The crude 2- amino 4 bromo-6-methylsulfonylbenzothiazol obtained melts at 278. It is insoluble in alcohol and only slightly of the bisphenylcarbarnic acid ester of 3-chloro-N.N-diQhy droXyethyD-aminobenzene in 50 parts of acetic acid is addsoluble in hot glacial acetic acid. The crude product ed and the coupling reaction is accelerated by the dropwise contains 24.96% of bromine, while the theoretical value addition of 400 parts of water whereby the resulting new for the chemically pure compound 15 26%. dyestufi 1S precipitated. It IS filtered off, washed free In the following Table 2 further monoazo dyestuffs from acid, dried and ground. The described procedure are recited which may be produced in an analogous manyields a red dyestufi which dyes cellulose acetate in the ner and which correspond to the formula mass in very brilliant bluish red shades which possess 3 very good fastness to light, washing, cross dyeing, gas R -o s fumes, oxylic acid, dry cleaning, and peroxide bleaching.

C-N=N-C N The dyeings are also stable to hydrosulfite. Ri- I 100 parts of cellulose acetate are mixed for a short I N Y time with 300 parts of a mixture of solvents (93% ace- Hfll tone and 7% methanol) and left overnight to swell.

Table 2 Ex. R1 R2 R3 R4 M Y Hal Shade No. 7

62 CH: GHQ-0N CH3 H H H 01 Pink." 63... 02114 CHzON CH3 H H H 01 D0. 64 CGHG GHiCN 0H1 H H H 01 Do. 65... CiHs GHQ-ON CHa H H H 01 D0. 66..- CiHi CHT-CN CH: H H CH3 01 Red violet 67.-. CH2 GHQ-0N CH3 H H H Br Pink. 68 C2H4 CHz-CN CH3 H H H Br Do. 69 CH3 CH2ON CH3 H H CH3 Br Red Violet 70 CZH-i CH CN CH3 H H CH3 Br Do. 71"-.- O2H4 CHiCN CEHE H 0H 01 Pink. 72 02H; CHg-ON 03111 H H CH3 Br Red violet. i 73 (Jim GHQ-0N CiHi H H 01 Br Red. 74 CzH CHr-CN CHzCH=CHz H OH BI 01 Red. 75 (3 114 GHQ-ON CH3 mm H CE 01 Red. 76-.. CiHi GHQ-ON NHOH:; H H Cl Pink. 77 02114 GHQ-ON N'HCH; H H CH3 Br Red violet 7a-.-. C2H4 CHg-CN NH-C2H6 H H 01 Pink.

NEE-C2115 H H CzHs Br Red violet N(CH3)2 H H OCH; C1 D0. N(CH3)2 H H H Br Pink. N(OHa)i H H CH3 C1 Red violet N(C2H5)2 (EH5 H H C]. Pink.

C3H1 H H CHa Br Red violet NH-OiHi H H H 01 Monti); H H OH; Br Red violet H3 H OCHs H 01 Pink. N(CH3)2 H O C2115 CH: 01 Red violet. NH(CH3) H O-CO-OHa Br Pink. 01120-0 O-C;H5 N(C2H5)3 H oc O-C2H5 CHa 01 Red violet. CH2OC 0-C2H5 3 H OC0C2H5 B1 Pink. CH2OC O-GH3 N(CH3)2 H O-C O-GHs OH: Br Red violet 93"-.- 02H; CH2-0C 0--C2H5 NH(OH3) H O-COC2H5 H Br 94 @2114 CH2OO OCH3 N( 2 5)a H O -CO-CHs CH: Br Redviolet 95"... CiHi CHg-O-C 0NH-0iHi a H OO 0NHOiHi 0H3 Bl' Do. 96 C2H4 CHr-O-C ONH-CQH5 N(CH3)2 H OC 0NHC2H5 CH3 Br D0, 97--. CzHi CHr-OH NH(CHZ) H H CH3 Br D0. 9s oiHi O1HiOH N(C:H )z H H GHa B1 Do. 99 our; O3H OH H3 H H CH3 Br Do. 100.. (Jim CH2- N(CH3 H 0H CH3 Bl Do. 101 oiHi C2H$-OO O-GH NH(CH3) H OCO-CH; NH-O0-CH3 Br Do. 102 OaHu C2Hi- N(CzH5)2 H OH NHCO--CHa B1 Violet. 103..-. OiHi GHQ-OH 3 H H NHC 0 -OF3 Br Do. 104---- C2114 0H oH)CH20H N(CH3)2 H H NHC OCH3 Br Do. 105 CzHi oHi-0H NH(CH3) H OH NH-C O-GZHs 01 Do. 106.... (3211i OHz-O-COOH3 N(CH3)2 H O-CO-OH3 NH-'C0 O2H5 Br Red violet 107-- C2114 CHz-OC 0CHi0-CHa Ha H O-COCHzOCH H Br 108. G211; UHF: N(OH3)2 H H CH3 Bl D0.

CHF; NH(CH3) H O-GO-CHs H Br Red. CFs (C2Hs)a H H CH: Br Pink. CF; CH3 H O-GO-CHa H Br Red. CHzCFa N(CHa)i H H CH: Br Pink. GH(OFS)CN NH(CH3) H 0Co-CH3 H Br Red. C2H4ON M02115; H H 0B3 01 Red violet CHFB 3 H OH H Cl Pink. CH -CN N(CH3)Z H 0-00-0113 H Br Red. GHi-CN NH(CH3) H 0-00-0113 H Br Red. GE -0N N(C;H )g H O-GO-OH: H Br Red. GHQ-0N CH3 H O-C 0OHi H Br Red. CHr-CN N(CH3)2 H 0-0 O-GHi CHa Br Pink.

Example 121: 15.35 parts of Z-amino-4-bromo-6-methylsulfonylbenzothiazol are dissolved in 400 parts of 85% phosphoric acid at 0. To the solution thus obtained nitroxylsulfuric acid prepared from 45 parts of concentrated Next day !1 part of the above dyestuff is dissolved in 60 parts of the same solvent mixture by simple shaking and the solution added to the main solution. The whole is 75 stirred in an open mixing kettle until 60 parts of the sol- Table 3.Continued Ex. R; R: R, R5 M I Shade No. r 1 1 14s.... CaHt CHrO-CO-NH-OCBH" M0133); Br -O-CO-NH-C -C5H11' Pink- 149.... 0 H; CHrO-C O-CH1 M04119), (:1 OCOCH3 Red. 150.... 02114 0117-0430-0113 NH-CaHn Br 0-00-0133 Red. 151.... 02114 om-o-o 0-0111 N(C12H25)2 Br 0COCH= Red.

152.... G211; CHq-O-C 0-0235 C3111 Br OC0C2H 'Red.

153.... 02H; GHQ-0N M0411), Br OOO-CH@ Red. 154.... 0,114 GHQ-ON CH: Br -OCO-CH: Red. 155.... G211; GHQ-(3N Nwm-cm-on Br -0-0 O-GH; R d.

" 0H 7 156.... 02114 CHz-CN Mom-c Br OC O-OHa Red. 7

Further dyestufis which are suitable for dyeing cellulose acetate fibers in the dope correspond to the formula Example 157:

H:O\ S

/CHaCHzO-C 0-0H:

C-N=N -N H3O N/ CH1CH2O-C O-GH; NH-CQ-(CH2)B-CH3 and Example 158:

H:G\ S

N ozs /OH2-CH2OGO-CH;

C-N=N N HaC I cH1-oH=0-o0-oH= NH-C O-GnHau 'Formulae of representative dyestufis of the foregoing Example 127: examples are as follows.

Example 49:

. S OHr-OHz-O-CO H: 8 p H1O 01S N=N O N oH=-orI,-o-oo-NH t om-om-wc o 0 O OH CH O-CO-NH 1 HN-C 0-0111: 0H, 50 N n r r Br Example 70:

. I S HSC OQS /CH2CH:

'N=N-C N Having thus d1sclosed the invention what we claim 1s: N l CHPCHPCN l. Monoazo dyestufl of the benzothiazol series of the formula S z Example 89: Rhms l R1 7 CH; 7 CN=N N HsG\ S o,5 CHz-CHz-O-OO \N V V R, I l H3O r R5 1 N GHrCHTWCIm wherein V Br CH3 R is a member selected from the group consisting of methyl, ethyl, acetoxyethyl, hydroxyethyl and Example p G v NHCO0--CHr-CH2 mo S CHa-CHa-O-CO R is a member selected from the group consisting of acetoxyethyl, cyanethyl, hydroxyethyl, dihydroxy: H36 propyl and N I CHrCHrO-CO V I HN-C Q-UaHa 1 Br 0H; ---NHCO--OCH:-OH:

13 14 R is a member selected from the group consisting of 4. The monoazo dyestufi of the benzothiazol series methyl, ethyl, dimethylamino and diethylamino, which corresponds to the formula Hag S CH1 CHhCHfl-O-CO H3O CN=N N\ om-orn-o-co I N HN-COC2H5 Br CH3 R is a member selcted from the group consisting of 5. The monoazo dyestufi of the benzothiazol series chlorine and bromine, which corresponds to the formula H3O S I NOzS- oHt0Ht-o c0-NH H3O CN=N N\ onhorrho-oo-Nn l N 01 l Br y is a member selected from the group consisting of hydrogen, chlorine, methyl, ethyl, acetylamino and 6. A monoazo dy-estufl of the benzothiazol series propionylamino and which corresponds to the formula z is a meber selcted from the group consisting of hy- S drogen, methoxy and ethoxy. 30 Rroas CHr-CH; 2. The monoazo dyestufi of the benzothiazol series which corresponds to the formula \CHPCHPCN S N lower alkyl /CHz-CH3 35 B wherein R represents alkyl with 1 to 4 carbon atoms. N l H H 7. A monoazo dyestufi of the benzthiazol series which Br corresponds to the formula lower alkyl\ S N-02S lower elkyl C N=N N All 3. The monoazo dyestufi of the benzothiazol series wherein each of the lower alkyl groups has maximally 12 which corresponds to the formula carbon atoms. H3 C\ s N O2S /CH2CH2O-CO CHr-CH2OCO Ba CH3 References Cited in the file of this patent UNITED STATES PATENTS 2,889,315 Boss'ard et a1 June 2, 1959 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,105,829 October 1, 1963 Ernest Marian et a1.

It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 3, line 11, for "spltitable" read splittable column 4, line 15, for "acetylaminobnezene" read acetylaminobenzene column 7, lines 74 and 75, for "nitroxylsulfuric" read nitrosylsulphuric column 13, line 29, for "meber" read member same column 13, for that portion of the formula in claim 3 reading read Ba Br Signed and sealed this 9th day of June 1964.

(SEAL) Attest:

ERNEST W. SWIDER EDWARD J. BRENNER Attesting Officer Commissioner of Patents 

1. MONOAZO DYESTUFF OF THE BENZOTHIAZOL SERIES OF THE FORMULA 